I caught this dust devil while we were coming back from Joshua Tree National Park yesterday. We were on the western end of I-10 driving about 80 mph (speed limit is 75 mph). I guess all my years of taking pictures from a moving car have paid off! Not to mention a little help from Aperture to correct for the tinted window… and Topaz Clarity.

A dust devil, like a tornado, is a weather phenomenon. Dust devils form as a swirling updraft under sunny conditions during fair weather, rarely coming close to the intensity of a tornado. According to Wikipedia, certain conditions increase the likelihood of dust devil formation:

Flat barren terrain, desert or tarmac: Flat conditions increase the likelihood of the hot-air “fuel” being a near constant. Dusty or sandy conditions will cause particles to become caught up in the vortex, making the dust devil easily visible.

Clear skies or lightly cloudy conditions: The surface needs to absorb significant amounts of solar energy to heat the air near the surface and create ideal dust devil conditions.

Light or no wind and cool atmospheric temperature: The underlying factor for sustainability of a dust devil is the extreme difference in temperature between the near-surface air and the atmosphere. Windy conditions will destabilize the spinning effect.